Footwear

ABSTRACT

A method .[.for.]. .Iadd.of .Iaddend.producing an injection molded article comprises positioning pre-formed sections made of cloth or the like in the cavity of an injection mold, injecting the molten resinous material into the remainder of the cavity and cooling the material to a condition under which the latter is cured and integrally connected to the pre-positioned sections. The article produced by the above method comprises at least sections and connecting members adapted to connect said sections to each other.

The present invention relates to improvements of injection moldedarticle such as footwear, container and the like and a method therefor,more particularly to low cost but comfortable footwear integrally formedof synthetic resin material and other material such as cloth, leather orthe like.

A main object of the present invention is to provide a new injectionmolded article of which a portion or portions is made of thermoplasticresinous material and other portion or portions being of differentmaterial such as cloth, leather or the like, these portions beingintegrally assembled into an united article such as footwear, containeror the like without use of any adhesive agent or stitching up to eachother.

A further object of the present invention is to provide a novel footwearsuch as a sandal, a shoe or the like in which a sole portion thereof ismolded of thermoplastic resinous material, and an upper portion beingmade of different material from the former, such as porous woven cloth,skin, leather or the like, said sole and upper portions being formed asan integrally united footwear without use of any adhesive agent orstitching up to each other.

Another object of the present invention is to provide a novel footwearin which a sole portion is molded of thermoplastic resinous material,having a foaming interior adapted for providing resiliency and having anon-foamy outer layer adapted for providing durability and resistanceagainst deformation thereof.

A further essential object of the present invention is to provide animproved method for producing such articles.

Other objects and advantages of the present invention will appear fromthe following disclosure of preferred embodiments taken in connectionwith the attached drawings, in which:

FIG. 1 is a perspective view of the sandal according to the presentinvention;

FIG. 2 is a sectional view of the sandal taken along the line 2--2 inFIG. 1;

FIG. 3 is a longitudinal sectional view of a mold available forproducing the sandal;

FIG. 4 is an enlarged sectional view taken along the line 4--4 in FIG.3;

FIG. 5 is a sectional view similar to the FIG 4, but the band sectionsinserted into the fixed places with the mold;

FIG. 6 is a sectional view taken along the line 6--6 in FIG. 5;

FIG. 7 is a sectional view of other embodiment of the sandal accordingto the present invention;

FIG. 8 is a sectional view of a mold available for producing the sandalillustrated in FIG. 7;

FIG. 9 is a side view of the shoe according to the present invention;

FIG. 10 is a mold adapted for producing the shoe;

FIG. 11 is a sectional view taken along the line 11--11 in FIG. 10;

FIG. 12 is a perspective view of the container according to the presentinvention;

FIG. 13 is a sectional view adapted for producing the container;

FIG. 14 is a cross-sectional view taken along the line 14--14 in FIG.13;

FIG. 15 is a perspective view of the semi-boot according to the subjectinvention; and

FIG. 16 is a perspective view of the hand-bag according to the presentinvention.

Referring now to the drawings 1 and 2, a sandal is illustrated as anembodiment of the article according to the present invention.

The sandal 10 comprises a band member 11 formed of two band sections 11Aand 11B, and a base portion or sole member 12 having an unique uppersurface 12A formed in a curved shape in conformity with the back figureof the user's sole. The said sections 11A, 11B of the band member 11 aremade of flexible material such, for example, as porous woven or knittedcloth, skin, haired sheet, or leather, synthetic resin or the like andare integrally connected to each other at upper end thereof by means ofa connection 13. Each of other end portions or lower end portions of theband sections 11A, 11B is embedded into the matrix of the sole member 12so that the latter and the band member 11 are integrally connected toeach other. Preferably, side edges of the band sections 11A and 11B arecovered with loop-like flanges 14, respectively, which are integrallyformed with the sole member 12. The said flanges 14 and the connection13 are adhered to the band sections during forming process of the sandalwhile the process will be hereinafter represented in detail.

The sole member 12, preferably is provided with a foamy interior portion12B adapted for providing resiliency and a nonfoamy outer layer 12Cintegral therewith adapted for providing durability and resistanceagainst deformation of the sandal.

FIGS. 3 to 6 show a mold 15 for producing the sandal. The mold comprisesseveral mold sections, that is, upper mold section 16, a core moldsection 17 and a lower mold section 18. These sections are separablyassembled so as to define a molding chamber or cavity 19 therein. Thesaid cavity 19 includes a sole-molding chamber 20 adapted for producingthe sole member 12 of the sandal, a band-supporting spaces 21 to closelysupport therein the pre-formed band sections 11A and 11B, a pair offlange-forming chambers 22 adapted for producing the flanges 14 aroundthe sides of the band sections and a connection-forming chamber 23adapted for producing the connection between the adjacent edges of theband sections, said chambers being communicated to each other to allowthe flow of thermoplastic material applied into the cavity 19 through aduct 24. The said lower mold section 18 is supported to move towards upand down by plungers 30 which are actuated by suitable mechanical means(not shown), and the core mold section 17 also being removably supportedby the conventional suitable means (not shown).

In producing the sandal, the pre-formed band sections 11A and 11B of thedesired material such, for example, as porous woven cloth are positionedwithin the appropriate spaces 21 in the mold. In this case, the size ofeach band section is so defined that when each of the band sections arepositioned in the appropriate space 21 the adjacent edges or upper edgesof the sections 11A and 11B are protruded into the connection-formingchamber 23 as shown in FIG. 5, and the side edges of the sections beingprotruded into the flange-forming chambers 22 as shown in FIG. 6, whilethe lower portions of the sections being protruded into the sole-moldingchamber 20 as shown in FIG. 5. After positioning the sections 11A and11B, heated and molten thermoplastic resinous material which can beexpanded or foamed is injected from an injection molding apparatus (notshown) into the enlargeable cavity 19 through the duct 24.

The material within the cavity is then cooled and cured by makingheat-exchange to the mold 15 which may be cooled by means of theconventional cooling device mounted onto the mold, so that the flanges14 and the connection 13 which are made of said thermoplastic resinousmaterial integrally with the sole member 12 are fused to the appropriateedges of the band sections 11A and 11B without use of any adhesive agentthereby easily obtaining the sandal provided with the above-mentionedconstruction as illustrated in FIGS. 1 and 2.

A number of various thermoplastic resinous material may be applicable tothe novel foamed material utilized in the present invention. Withoutintending to be restricted thereto, however, the invention isparticularly adapted to be formed of granules of polystyrene. Theblowing agents employed for the expansible thermoplastic resinousmaterial may be those which are commonly utilized includingdichlorodifluoromethane, carbon dioxide, pentane and other low boilinghydrocarbons or other suitable materials such as sensitive gasgenerating agents and the like.

To form the foamed material, the preferred method comprises charging amass of the said granules into a dischargeable injection chamber of theinjection molding apparatus; then, in intermittent molding cycle,forcing said mass under pressure sequentially in and through a firstcold zone in said injection chamber wherein a portion of said mass iscompacted in solid granular form while being maintained at a temperaturebeneath its foaming temperature; a second heated zone adjacent to thefirst zone in said injection chamber wherein a portion of said mass isheated to a flowable condition under the application of an adequatequantity of heat to cause it to attain a foaming temperature; the solidcompacted portion of the mass in the first zone continuously maintainingthe heated portion of said mass in the second zone to restrainsubstantial foaming therein; and a discharge zone in said injectionchamber from which a portion of said heated mass is injected to fill theenlargeable cavity 19 wherein the injected mass is initially exteriorlycooled by the mold to form a solidified surface layer while beingmaintained under pressure; and finally relieving the pressure andenlarging the cavity to permit the central, relatively uncooled heatedmass to expand and force the solidified surface layer against theenlarged confining limit of the cavity to form said sandwichconstruction molded foam structure.

FIG. 7 shows a modified sandal according to the present invention inwhich a rear cover member 25 preferably made of fur or haired sheet isinseparably secured onto the back surface of the band member 11 so as tofacilitate the most suitable function even during the cold wintertogether with the enhanced comfort. In producing this typed sandal, therear cover member 25 is positioned in a spaces 21' of a mold 15'together with the band sections along the back surfaces thereof beforethe thermoplastic resinous material is injected into a cavity 19' of themold 15' as shown in FIG. 8. The mold 15' illustrated is FIG. 8 isconstructed in similar fashion to the mold 15, but distance betweeninner and outer surfaces of each of the spaces 21' is somewhat largerthan that of the space 21 to allow insertion of the rear cover member 25together with the band sections. Further, the inner surface of aconnection-forming chamber 23' is provided with a plurality of suctionopenings 26 which are communicated with a suitable vacuum pump (notshown) through a manifold 27 formed in the core mold sections 17. Thus,when the rear cover member 25 is inserted in the spaces 21' across theconnection-forming chamber 23', a central portion of the cover member 25sat in the chamber 23' may be downwardly withdrawn by feeding suctionair from the openings 26, whereby the cover member 25 can be mountedonto the back surface of the band member as shown in FIG. 7.

FIG. 9 shows the other embodiment of the article according to thepresent invention, embodying into a sports shoe 31. The shoe comprisesan upper 32 and a sole 33 which is made of similar material to the solemember of the sandal 15. The said upper 32 is consisted of severalsections, that is, a toe cap section 32A, side vamp sections 32B, anupper vamp section 32C and counter sections 32D, these sections beinginseparably jointed to each other at adjacent edges thereof by elongatedconnections 34 which are integrally formed with the sole 33. Preferably,the top cap section 32A and the counter sections 32D are formed ofrelatively strong material such, for example, as natural leather orsheet, reinforcing synthetic resin leather or sheet, or the like, andthe vamp sections being made of flexible and porous (meshy) leather orsheet such as woven cloth or the like for ventilation.

FIGS. 10 and 11 show a mold available for producing the shoe illustratedin FIG. 9 in which the mold 34 is provided with a cavity 35. The cavity35 includes a sole-forming chamber 35A, connection-forming grooves orchambers 35B and spaces 35C for closely inserting the upper sectionsthereinto. It will be understood that, by using the mold 34 and byprocessing similar manner to the first embodiment, the shoe 31illustrated in FIG. 9 may be easily produced.

Further, the method of the present invention is capable of producing acontainer as shown in FIG. 12 in which the container 40 comprises abottom plate 41 made of thermoplastic resinous material, verticalpillars 42 made of the same material with the plate 41 and upwardlyextending integrally from the each corner of the bottom plate 41, andside walls 43 made of different material from the bottom plate and thepillar such as wooden plate or sheet, steel plate or sheet, syntheticresin plate or sheet, meshy plate or sheet made of said suitablematerial, or the like, said walls being fixedly supported by the pillarsand the bottom plate.

FIGS. 13 and 14 show a mold available for producing the container inwhich the mold 44 is provided with a cavity 45 therein. The cavity 45includes a bottom-forming chamber 45A, pillar-forming chamber 45B andspaces 45C for closely inserting the side walls 45 thereinto. After theside walls 43 are inserted in the appropriate space as shown in FIGS. 13and 14, the molten thermoplastic resinous materials is injected into thechambers, and then the material being cooled whereby the containerformed of several components of different material may be obtained.

Some kind of semi-boot is also able to be produced according to theaforesaid method of the subject invention. For example, a semi-boot asshown in FIG. 15 produced by the process comprises an sole 47 and anupper 46 which is provided with a toe cap sections 48 made ofreinforcing material such as natural leather or sheet, synthetic resinleather or sheet, or the like, a counter sections 49 made of the same orsimilar material to said cap sections 48, lateral side sections 50 madeof flexible and porous (meshy) leather or sheet such as rough pitchedwoven or knitted cloth, perforated (porous) synthetic resin sheet orleather, or the like for ventilation, an outer eyelet reinforcement 51made of suitable material sheet or leather and said sections 48, 49, 50and reinforcement 51 being inseparably jointed to each other at adjacentedges thereof by means of connecting members 52 made of thermoplasticresin material and integrally connected to the sole 47. Also, a handbagas shown in FIG. 16 is to be produced according to the aforesaid methodof the present invention. And, for example, the said handbag comprisesfront section 53, rear section 54 which are made of flexible and porous(meshy) leather or sheet such as woven or knitted cloth, skin, hairedleather or sheet, synthetic resin leather or sheet, or the like whilethey may be made of the other leather or sheet as rough pitched woven orknitted cloth, perforated (porous) synthetic resin sheet or leather, orthe like, lateral side sections 55 made of same or similar leather orsheet to the sections 53, 54, a bottom member 56 made of suitableconventional sheet or leather, handles 57 and said sections 53, 54, 55being inseparably joined to each other at adjacent edges thereof bymeans of connecting members 58 made of thermoplastic resin material andintegrally connected to the bottom member 56.

While the present invention has been illustrated and described hereinwith respect to a preferred embodiment, it is not desired to limit theinvention only to the embodiment, but the invention should be consideredto include all the substitutes, modifications and equivalents which areencompassed within the essential part of the invention to be set forthin the scope of the underwritten claims and within the scope of thespirit exhibited in the invention of the inventor.

What I claim is:
 1. A footwear comprising a molded thermoplastic solehaving a pair of sides and an upper member having a pair of sections offlexible material, one of the sections of the upper member extendinginto the sole along one side thereof and being secured within the moldedsole, the other section of the upper extending into the sole along theother side thereof and being secured within the molded sole, thesections extending upwardly from opposite sides of the sole and towardeach other to form a band member, each of the sections having an edgeadjacent an edge of the other section, a cover member extending alongthe inner surfaces of the sections and being spaced from the sectionsadjacent the adjacent edges thereof, each pair of adjacent edges of thesections being secured by a molded thermoplastic connecting stripsurrounding the adjacent edges and extending therebetween and fillingthe space between the cover member and the sections and securing thecover member to the sections.
 2. A footwear comprising an upper memberincluding a plurality of sections and a sole member made ofthermoplastic resinous material, said sections being made of flexiblematerial and being integrally connected to each other at adjacent edgesthereof by at least one connecting member, an end portion of eachsection being connected to the edge portion of the sole member, saidsole member being provided with an upper surface formed in a curvedshape in conformity with the foot of the wearer and being provided witha foamy interior portion adapted for providing resilience and anon-foamy outer later integral therewith adapted for providingdurability and resistance against deformation of the footwear.
 3. Thefootwear of claim 2 wherein said upper is a band member, said bandmember being provided with a rear cover member inseparably secured ontothe back surface of the band member. .Iadd.
 4. In a shoe having an upperand a sole, the sole being formed of molded resinous material and havinga foamed inner layer and a non-foamy outer layer completely surroundingsaid foamed inner layer, the improvement wherein said upper comprises aplurality of upper sections and a connecting member formed of resinousmaterial, the upper sections including at least a toe cap section and acounter section formed of reinforcing material, said upper sectionsbeing connected to one another by said connecting member..Iaddend..Iadd.
 5. The shoe of claim 4 wherein said connecting member ismolded integrally with the sole and extends upwardly therefrom..Iaddend..Iadd.
 6. The shoe of claim 4 wherein a portion of saidshape-retaining and connecting member extends upwardly from the sole andis molded integrally therewith, the lower peripheral edge of the upperbeing connected to said portion. .Iaddend..Iadd.
 7. The shoe of claim 4wherein the upper includes an intermediate section between said toe capsection and counter section and connected thereto by the shape-retainingand connecting member, the intermediate section being formed of porousair-permeable material..Iaddend.